Technical Field
The present invention relates generally to the field of generating recombinant chimeric fusion proteins to be used in the cancer therapy, and more specifically, to fusion molecules of Anti-EGFR1-TGFβRII, Anti-EGFR1-PD1 and Anti-CTLA4-PD1 and methods of generating same, wherein the methods reduce production costs and increase homogeneity of the recombinant chimeric fusion proteins.
Related Art
In spite of numerous advances in medical research, cancer remains the second leading cause of death in the United States. Traditional modes of clinical care, such as surgical resection, radiotherapy and chemotherapy, have a significant failure rate, especially for solid tumors. Failure occurs either because the initial tumor is unresponsive, or because of recurrence due to regrowth at the original site or metastasis. Cancer remains a central focus for medical research and development.
Immunotherapy of cancer has been explored for over a century, but it is only in the last decade that various antibody-based products have been introduced into the management of patients with diverse forms of cancer. At present, this is one of the most active areas of clinical research, with numerous antibody therapeutic products already approved in oncology.
Using specific antibodies as therapeutic agents offers advantages over the non-targeted therapies such as systemic chemotherapy via oral or intravenous administration of drugs or radiation therapy. There are two types of antibody-based therapies. The more common type is to identify a tumor antigen (i.e., a protein expressed on tumors and cancer cells and not in normal tissues) and develop an antibody, preferably a monoclonal antibody (mAb) directed to the tumor antigen. One can then conjugate any therapeutic agent, such as a chemotherapeutic agent, a radionuclide, modified toxin, etc., to this antibody to achieve targeted therapy by the therapeutic agent to the tumor. The other kind of antibody based therapy is by providing an antibody which in itself has therapeutic properties against the tumor/cancer cells it targets. The added advantage of this second form of antibody-based therapy is that one may additionally conjugate another therapeutic agent to the therapeutic antibody to achieve a more effective treatment. The major advantage with any antibody-directed therapy and of therapy using monoclonal antibodies (mAbs) in particular, is the ability to deliver increased doses of a therapeutic agent to a tumor, with greater sparing of normal tissue from the side effects of the therapeutic agent.
Despite the identification of several antibodies for cancer therapies, there is still a need to identify new and more effective therapeutics to overcome immune tolerance and activate T cell responses. Further, even though molecular engineering has improved the prospects for such antibody-based therapeutics issues still remain regarding continuity in the generated recombinant products.